Monsoon Season in Arizona:

Monsoon Season in Arizona: What to Expect for Summer 2025

As the temperatures climb into the triple digits, afternoon winds pick up, and dramatic thunderheads begin to build over the mountains, it's clear that monsoon season in Arizona is on the horizon.

What is the Monsoon Season?
Officially, the National Weather Service designates June 15 through September 30 as monsoon season in Arizona. While June is typically the driest month of the year, the true start of monsoon activity depends on a few key environmental indicators.

2025 Monsoon Outlook

According to the National Weather Service, the 2025 monsoon season is forecasted to be slightly above average, with more widespread storm activity expected across Central Arizona, including Fountain Hills, Scottsdale, and the greater Phoenix Valley. With a wetter and more active pattern forming in the eastern Pacific and higher-than-average dew point projections, this year could bring much-needed rainfall and some spectacular desert lightning shows.

The El Niño conditions that developed in late 2024 have carried over, creating favorable atmospheric conditions for enhanced storm development in the Southwest. That means we may experience more frequent storms, higher humidity, and increased rainfall totals compared to previous years.

When Does the Monsoon Begin?

While June 15 is the official start, meteorologists look for three consecutive nights with dew points above 55°F to signal the monsoon's true arrival. Once that moisture builds in the atmosphere, the intense afternoon heat can trigger towering storm clouds and, eventually, rain, wind, and lightning.

Nature’s Early Warning Signs

Besides weather data, nature often gives us clues that storms are coming:

• Cicadas begin chirping during the hottest and driest part of the season, typically just before storms arrive.
• Afternoon winds pick up speed and direction changes.
• Dramatic cloud formations build over the McDowell Mountains and Four Peaks.

Adero Canyon Ridgeline Trail

Local Impact in Fountain Hills

In years with strong monsoon activity, early morning fog and low cloud cover have even blanketed parts of the McDowell Mountains, offering a surreal sight in the desert landscape.

While monsoon storms are thrilling to watch, they can also bring sudden flash flooding, dust storms (haboobs), and power outages. If you’re new to the area, be sure to familiarize yourself with monsoon safety tips and always check the forecast before heading out on hikes or road trips.